I *think* I have done enough research and reviewing of products and recommendations but i would certainly appreciate your feedback on what I have come up with. Mainly a gaming system with some photoshopping.
I have mouse/keyboard and HD monitor (HP w2408h) already.
The thing that would make the most improvement would be the video card and it would only be realized when playing a game and of course it would depend on how much extra cash you had. This is still a 560Ti but it is the 448 cores one.
I calculated your total to be around $1500, so you still have $500 more to spend, or maybe less if Windows 7 is also required to fit in the 2k budget. You should go for two GTX 570's in SLI and get a more powerful PSU to support it. Two GTX 570's and a PSU upgrade that you should probably get will bring the total to around $1850, so you will have enough money left for Windows.
I recommend: This GTX 570 if it gets back in stock Otherwise this one which is a little more expensive
At least get some GPU with a blower style cooling, as those work better for SLI. A good 1000W PSU
If Windows isn't in your budget, you can always use the remaining money to get a better case, like the Corsair 500R, a better heatsink, like the NH-D14, or a better SSD (larger)